1) I saw there are functions to export data from CSV our XLS file. I cannot find the menu on the demo mode. Is the menu exist and if yes where is it?

Import is disabled in Demo as it is an admin feature.
But it really exists and works fine.

2) May I consider that is possible to import data when menu to export exit (in a particular menu) ? For instance there is a menu export in the menu resource, so may I consider it is possible to import resource if I can export?

Yes.
And exported format can directly be re-imported. So you can for instance use it for mass updates.

3) If response for 2) is yes, is it possible to import data for one resource with the cost of the ressource for instance ?

Import works object per object.
So you have to import Resource.
Then import resource cost.

How to enable import menu for user?
(We have a local installed version of Projeqtor. Is it in DEMO mode? )
Thank you
Q D

Manage access rights to screen.